Late in 1942, work was well advanced at the MiG bureau on several aircraft in parallel and referred to as Series "A" prototypes, with which the OKB hoped to fulfil a VP (vysotny perekhvatchik, or high-altitude interceptor) requirement raised earlier in the year.
The second Series "A" high-altitude fighter and referred to as the 2A, the I-221 was the first of the OKB's fighter prototypes to be fitted with turbo-superchargers. The I-221 was fitted with an AM-39A engine rated at 1700hp for take-off and equipped with a centrifugal compressor and paired TsIAM-developed TK-2B turbo-superchargers which, it was anticipated, would permit maximum power to be maintained to an altitude of 13000m. Although adhering closely in most other respects to the preceding I-220, the I-221 had a rear fuselage of dural construction rather than a wooden monocoque, and the outer wing panels were extended, increasing span by a total of 2.00m. Armament consisted of two synchronised 20mm cannon. The initial flight test took place on 2 December 1943, but the programme came to an abrupt end when, during one of the prototype's early trials, a piston rod fractured, the engine seized and the aircraft crashed.